IPv4 Subnet Calculator

Enter an IP with a CIDR prefix or a subnet mask to see its network, broadcast, host range, and host count. You can also split the network into smaller subnets.

Try:192.168.1.10/24 10.0.0.0/8 172.16.5.4/20 203.0.113.9/29

IPv6 calculator →

private IP (RFC 1918)10.3.206.0/25

network10.3.206.0/25

broadcast10.3.206.127

first host10.3.206.1

last host10.3.206.126

subnet mask255.255.255.128

wildcard0.0.0.127

addresses128

usable hosts126

classA

ipcalc 10.3.206.0/25

address00001010.00000011.11001110.00000000

subnet mask11111111.11111111.11111111.10000000

network00001010.00000011.11001110.00000000

broadcast00001010.00000011.11001110.01111111

green = network part, grey = host part

hex0x0a03ce00

decimal168021504

reverse dns0.206.3.10.in-addr.arpa

ipv4-mapped::ffff:a03:ce00

/25 split into /32 · 128 subnets

close ×

#	network	host range	broadcast
1	10.3.206.0/32	10.3.206.0 – 10.3.206.0	10.3.206.0
2	10.3.206.1/32	10.3.206.1 – 10.3.206.1	10.3.206.1
3	10.3.206.2/32	10.3.206.2 – 10.3.206.2	10.3.206.2
4	10.3.206.3/32	10.3.206.3 – 10.3.206.3	10.3.206.3
5	10.3.206.4/32	10.3.206.4 – 10.3.206.4	10.3.206.4
6	10.3.206.5/32	10.3.206.5 – 10.3.206.5	10.3.206.5
7	10.3.206.6/32	10.3.206.6 – 10.3.206.6	10.3.206.6
8	10.3.206.7/32	10.3.206.7 – 10.3.206.7	10.3.206.7
9	10.3.206.8/32	10.3.206.8 – 10.3.206.8	10.3.206.8
10	10.3.206.9/32	10.3.206.9 – 10.3.206.9	10.3.206.9
11	10.3.206.10/32	10.3.206.10 – 10.3.206.10	10.3.206.10
12	10.3.206.11/32	10.3.206.11 – 10.3.206.11	10.3.206.11
13	10.3.206.12/32	10.3.206.12 – 10.3.206.12	10.3.206.12
14	10.3.206.13/32	10.3.206.13 – 10.3.206.13	10.3.206.13
15	10.3.206.14/32	10.3.206.14 – 10.3.206.14	10.3.206.14
16	10.3.206.15/32	10.3.206.15 – 10.3.206.15	10.3.206.15
17	10.3.206.16/32	10.3.206.16 – 10.3.206.16	10.3.206.16
18	10.3.206.17/32	10.3.206.17 – 10.3.206.17	10.3.206.17
19	10.3.206.18/32	10.3.206.18 – 10.3.206.18	10.3.206.18
20	10.3.206.19/32	10.3.206.19 – 10.3.206.19	10.3.206.19
21	10.3.206.20/32	10.3.206.20 – 10.3.206.20	10.3.206.20
22	10.3.206.21/32	10.3.206.21 – 10.3.206.21	10.3.206.21
23	10.3.206.22/32	10.3.206.22 – 10.3.206.22	10.3.206.22
24	10.3.206.23/32	10.3.206.23 – 10.3.206.23	10.3.206.23
25	10.3.206.24/32	10.3.206.24 – 10.3.206.24	10.3.206.24
26	10.3.206.25/32	10.3.206.25 – 10.3.206.25	10.3.206.25
27	10.3.206.26/32	10.3.206.26 – 10.3.206.26	10.3.206.26
28	10.3.206.27/32	10.3.206.27 – 10.3.206.27	10.3.206.27
29	10.3.206.28/32	10.3.206.28 – 10.3.206.28	10.3.206.28
30	10.3.206.29/32	10.3.206.29 – 10.3.206.29	10.3.206.29
31	10.3.206.30/32	10.3.206.30 – 10.3.206.30	10.3.206.30
32	10.3.206.31/32	10.3.206.31 – 10.3.206.31	10.3.206.31
33	10.3.206.32/32	10.3.206.32 – 10.3.206.32	10.3.206.32
34	10.3.206.33/32	10.3.206.33 – 10.3.206.33	10.3.206.33
35	10.3.206.34/32	10.3.206.34 – 10.3.206.34	10.3.206.34
36	10.3.206.35/32	10.3.206.35 – 10.3.206.35	10.3.206.35
37	10.3.206.36/32	10.3.206.36 – 10.3.206.36	10.3.206.36
38	10.3.206.37/32	10.3.206.37 – 10.3.206.37	10.3.206.37
39	10.3.206.38/32	10.3.206.38 – 10.3.206.38	10.3.206.38
40	10.3.206.39/32	10.3.206.39 – 10.3.206.39	10.3.206.39
41	10.3.206.40/32	10.3.206.40 – 10.3.206.40	10.3.206.40
42	10.3.206.41/32	10.3.206.41 – 10.3.206.41	10.3.206.41
43	10.3.206.42/32	10.3.206.42 – 10.3.206.42	10.3.206.42
44	10.3.206.43/32	10.3.206.43 – 10.3.206.43	10.3.206.43
45	10.3.206.44/32	10.3.206.44 – 10.3.206.44	10.3.206.44
46	10.3.206.45/32	10.3.206.45 – 10.3.206.45	10.3.206.45
47	10.3.206.46/32	10.3.206.46 – 10.3.206.46	10.3.206.46
48	10.3.206.47/32	10.3.206.47 – 10.3.206.47	10.3.206.47
49	10.3.206.48/32	10.3.206.48 – 10.3.206.48	10.3.206.48
50	10.3.206.49/32	10.3.206.49 – 10.3.206.49	10.3.206.49
51	10.3.206.50/32	10.3.206.50 – 10.3.206.50	10.3.206.50
52	10.3.206.51/32	10.3.206.51 – 10.3.206.51	10.3.206.51
53	10.3.206.52/32	10.3.206.52 – 10.3.206.52	10.3.206.52
54	10.3.206.53/32	10.3.206.53 – 10.3.206.53	10.3.206.53
55	10.3.206.54/32	10.3.206.54 – 10.3.206.54	10.3.206.54
56	10.3.206.55/32	10.3.206.55 – 10.3.206.55	10.3.206.55
57	10.3.206.56/32	10.3.206.56 – 10.3.206.56	10.3.206.56
58	10.3.206.57/32	10.3.206.57 – 10.3.206.57	10.3.206.57
59	10.3.206.58/32	10.3.206.58 – 10.3.206.58	10.3.206.58
60	10.3.206.59/32	10.3.206.59 – 10.3.206.59	10.3.206.59
61	10.3.206.60/32	10.3.206.60 – 10.3.206.60	10.3.206.60
62	10.3.206.61/32	10.3.206.61 – 10.3.206.61	10.3.206.61
63	10.3.206.62/32	10.3.206.62 – 10.3.206.62	10.3.206.62
64	10.3.206.63/32	10.3.206.63 – 10.3.206.63	10.3.206.63
65	10.3.206.64/32	10.3.206.64 – 10.3.206.64	10.3.206.64
66	10.3.206.65/32	10.3.206.65 – 10.3.206.65	10.3.206.65
67	10.3.206.66/32	10.3.206.66 – 10.3.206.66	10.3.206.66
68	10.3.206.67/32	10.3.206.67 – 10.3.206.67	10.3.206.67
69	10.3.206.68/32	10.3.206.68 – 10.3.206.68	10.3.206.68
70	10.3.206.69/32	10.3.206.69 – 10.3.206.69	10.3.206.69
71	10.3.206.70/32	10.3.206.70 – 10.3.206.70	10.3.206.70
72	10.3.206.71/32	10.3.206.71 – 10.3.206.71	10.3.206.71
73	10.3.206.72/32	10.3.206.72 – 10.3.206.72	10.3.206.72
74	10.3.206.73/32	10.3.206.73 – 10.3.206.73	10.3.206.73
75	10.3.206.74/32	10.3.206.74 – 10.3.206.74	10.3.206.74
76	10.3.206.75/32	10.3.206.75 – 10.3.206.75	10.3.206.75
77	10.3.206.76/32	10.3.206.76 – 10.3.206.76	10.3.206.76
78	10.3.206.77/32	10.3.206.77 – 10.3.206.77	10.3.206.77
79	10.3.206.78/32	10.3.206.78 – 10.3.206.78	10.3.206.78
80	10.3.206.79/32	10.3.206.79 – 10.3.206.79	10.3.206.79
81	10.3.206.80/32	10.3.206.80 – 10.3.206.80	10.3.206.80
82	10.3.206.81/32	10.3.206.81 – 10.3.206.81	10.3.206.81
83	10.3.206.82/32	10.3.206.82 – 10.3.206.82	10.3.206.82
84	10.3.206.83/32	10.3.206.83 – 10.3.206.83	10.3.206.83
85	10.3.206.84/32	10.3.206.84 – 10.3.206.84	10.3.206.84
86	10.3.206.85/32	10.3.206.85 – 10.3.206.85	10.3.206.85
87	10.3.206.86/32	10.3.206.86 – 10.3.206.86	10.3.206.86
88	10.3.206.87/32	10.3.206.87 – 10.3.206.87	10.3.206.87
89	10.3.206.88/32	10.3.206.88 – 10.3.206.88	10.3.206.88
90	10.3.206.89/32	10.3.206.89 – 10.3.206.89	10.3.206.89
91	10.3.206.90/32	10.3.206.90 – 10.3.206.90	10.3.206.90
92	10.3.206.91/32	10.3.206.91 – 10.3.206.91	10.3.206.91
93	10.3.206.92/32	10.3.206.92 – 10.3.206.92	10.3.206.92
94	10.3.206.93/32	10.3.206.93 – 10.3.206.93	10.3.206.93
95	10.3.206.94/32	10.3.206.94 – 10.3.206.94	10.3.206.94
96	10.3.206.95/32	10.3.206.95 – 10.3.206.95	10.3.206.95
97	10.3.206.96/32	10.3.206.96 – 10.3.206.96	10.3.206.96
98	10.3.206.97/32	10.3.206.97 – 10.3.206.97	10.3.206.97
99	10.3.206.98/32	10.3.206.98 – 10.3.206.98	10.3.206.98
100	10.3.206.99/32	10.3.206.99 – 10.3.206.99	10.3.206.99
101	10.3.206.100/32	10.3.206.100 – 10.3.206.100	10.3.206.100
102	10.3.206.101/32	10.3.206.101 – 10.3.206.101	10.3.206.101
103	10.3.206.102/32	10.3.206.102 – 10.3.206.102	10.3.206.102
104	10.3.206.103/32	10.3.206.103 – 10.3.206.103	10.3.206.103
105	10.3.206.104/32	10.3.206.104 – 10.3.206.104	10.3.206.104
106	10.3.206.105/32	10.3.206.105 – 10.3.206.105	10.3.206.105
107	10.3.206.106/32	10.3.206.106 – 10.3.206.106	10.3.206.106
108	10.3.206.107/32	10.3.206.107 – 10.3.206.107	10.3.206.107
109	10.3.206.108/32	10.3.206.108 – 10.3.206.108	10.3.206.108
110	10.3.206.109/32	10.3.206.109 – 10.3.206.109	10.3.206.109
111	10.3.206.110/32	10.3.206.110 – 10.3.206.110	10.3.206.110
112	10.3.206.111/32	10.3.206.111 – 10.3.206.111	10.3.206.111
113	10.3.206.112/32	10.3.206.112 – 10.3.206.112	10.3.206.112
114	10.3.206.113/32	10.3.206.113 – 10.3.206.113	10.3.206.113
115	10.3.206.114/32	10.3.206.114 – 10.3.206.114	10.3.206.114
116	10.3.206.115/32	10.3.206.115 – 10.3.206.115	10.3.206.115
117	10.3.206.116/32	10.3.206.116 – 10.3.206.116	10.3.206.116
118	10.3.206.117/32	10.3.206.117 – 10.3.206.117	10.3.206.117
119	10.3.206.118/32	10.3.206.118 – 10.3.206.118	10.3.206.118
120	10.3.206.119/32	10.3.206.119 – 10.3.206.119	10.3.206.119
121	10.3.206.120/32	10.3.206.120 – 10.3.206.120	10.3.206.120
122	10.3.206.121/32	10.3.206.121 – 10.3.206.121	10.3.206.121
123	10.3.206.122/32	10.3.206.122 – 10.3.206.122	10.3.206.122
124	10.3.206.123/32	10.3.206.123 – 10.3.206.123	10.3.206.123
125	10.3.206.124/32	10.3.206.124 – 10.3.206.124	10.3.206.124
126	10.3.206.125/32	10.3.206.125 – 10.3.206.125	10.3.206.125
127	10.3.206.126/32	10.3.206.126 – 10.3.206.126	10.3.206.126
128	10.3.206.127/32	10.3.206.127 – 10.3.206.127	10.3.206.127

01 / table

IPv4 CIDR prefix table.

Click a prefix longer than your network to split it into subnets.

prefix	subnet mask	addresses	hosts	in your /25
/0	0.0.0.0	4,294,967,296	4,294,967,294	-
/1	128.0.0.0	2,147,483,648	2,147,483,646	-
/2	192.0.0.0	1,073,741,824	1,073,741,822	-
/3	224.0.0.0	536,870,912	536,870,910	-
/4	240.0.0.0	268,435,456	268,435,454	-
/5	248.0.0.0	134,217,728	134,217,726	-
/6	252.0.0.0	67,108,864	67,108,862	-
/7	254.0.0.0	33,554,432	33,554,430	-
/8	255.0.0.0	16,777,216	16,777,214	-
/9	255.128.0.0	8,388,608	8,388,606	-
/10	255.192.0.0	4,194,304	4,194,302	-
/11	255.224.0.0	2,097,152	2,097,150	-
/12	255.240.0.0	1,048,576	1,048,574	-
/13	255.248.0.0	524,288	524,286	-
/14	255.252.0.0	262,144	262,142	-
/15	255.254.0.0	131,072	131,070	-
/16	255.255.0.0	65,536	65,534	-
/17	255.255.128.0	32,768	32,766	-
/18	255.255.192.0	16,384	16,382	-
/19	255.255.224.0	8,192	8,190	-
/20	255.255.240.0	4,096	4,094	-
/21	255.255.248.0	2,048	2,046	-
/22	255.255.252.0	1,024	1,022	-
/23	255.255.254.0	512	510	-
/24	255.255.255.0	256	254	-
/25	255.255.255.128	128	126	1
/26	255.255.255.192	64	62	2 split →
/27	255.255.255.224	32	30	4 split →
/28	255.255.255.240	16	14	8 split →
/29	255.255.255.248	8	6	16 split →
/30	255.255.255.252	4	2	32 split →
/31	255.255.255.254	2	2	64 split →
/32	255.255.255.255	1	1	128 split →

02 / faq

About this calculator.

How do I use this subnet calculator?

▼

Type an IP address followed by a prefix, like 192.168.1.10/24, or by a subnet mask, like 192.168.1.10 255.255.255.0. Without a prefix it uses /24. Click a row in the table to split the network into smaller subnets.

Why are usable hosts always 2 fewer?

▼

The first address in a subnet is the network address and the last is the broadcast address, so neither can go to a device. The exceptions are /31 (point-to-point links, RFC 3021) and /32 (a single address), which use every address.

Can I use it from a terminal?

▼

Yes. curl 'ipku.in/en/tools/ipv4-subnet-calculator?q=192.168.1.10/24' returns the result as plain text.

Learn how to work it out →